code: def __init__(self, simd_width):
      self.simd_width = simd_width
      if simd_width % 32 != 0:
          raise ("SIMD bit width should be a multiple of 32")
      self.simd_byte_width = simd_width // 8
  
file_path: arrow/cpp/src/arrow/util/bpacking_simd_codegen.py
imports: from functools import partial
  import sys
  from textwrap import dedent, indent
label_desc: Use image node_id 1 to create a new UnpackGenerator object  with example: obj = UnpackGenerator(simd_width)